[dataimport] introduce the importer and extentity classes This introduces the ``ExtEntity`` class which is a transitional state between data at external source and the actual CubicWeb entities. ``ExtEntitiesImporter`` is then in charge to turn a bunch of ext entities into CW entities in repository, using a given store. This changeset also introduces ``SimpleImportLog`` and ``HTMLImportLog`` which implement the CW DataImportLog interface in order to show log messages in UI using simple text and HTML formats respectively, instead of storing these messages in database. Both have mostly been backported from cubes.skos.dataimport. Closes #5414753.

[test] Use store.prepare_insert_relation instead of deprecated relate method Follow-up for 1f5026e7d848. Related to #5040344.

[dataimport] since we have foreign key constraints in the database, 'entities' table should be updated first

[dataimport] Move stores to new API. Here is the final store API: * ``prepare_insert_entity(<entity type>, **kwargs) -> eid``: given an entity type, attributes and inlined relations, return the eid of the entity to be inserted, *with no guarantee that anything has been inserted in database*, * ``prepare_update_entity(<entity type>, eid, **kwargs) -> None``: given an entity type and eid, promise for update given attributes and inlined relations *with no guarantee that anything has been inserted in database*, * ``prepare_insert_relation(eid_from, rtype, eid_to) -> None``: indicate that a relation ``rtype`` should be added between entities with eids ``eid_from`` and ``eid_to``. Similarly to ``prepare_insert_entity()``, *there is no guarantee that the relation will be inserted in database*, * ``flush() -> None``: flush any temporary data to database. May be called several times during an import, * ``finish() -> None``: additional stuff to do after import is terminated. **Warning:** ``prepare_update_entity()`` still needs to be implemented for NoHookRQLObjectStore. Related to #5040344

[js] Using appropriate http method when calling a remote function to respect REST principles. closes #5355952

[server/test] Add a test for db-statement-timeout option Sadly I don't think there's a way to test that functionality without adding sleeps which make the test suite longer :/ Related to #2547026

[datafeed] give an error message if a source is missing a parser id Closes #3484231

[storage] use mkstemp to create files in bfss Avoids race condition, at the cost of slightly less predictable file names.

[test] Skip spa2rql tests when fyzz is not available Closes #5456750.

[web/staticcontrollers] fix docstring spelling

[server/rql2sql] fix spelling in comment Not that I understand what that sentence means.

[doc/book] fix rql syntax examples "Any", not "ANY". "EXISTS" is a function.

[migration] add sql constraints on upgrade Related to #5154406.

[schema] neuter check method for constraints we implement in sql Closes #5154406.

add IUserFriendlyError adapter for violation of check constraints This way we get back the same error messages we get from the python check. Related to #5154406

[hooks/syncschema] drop/add check constraints as appropriate Related to #5154406

[schema2sql] support NOW and TODAY in check constraints Related to #5154406.

[schema2sql] insert some constraints into the backend BoundaryConstraint, IntervalBoundConstraint and StaticVocabularyConstraint can be implemented in SQL with CHECK constraints. Next steps, not part of this changeset: - migrations - removing no longer necessary pre-insertion work on the python side - translating backend exception due to constraint violation into ValidationError Note: this means that these constraints can no longer be ignored by disabling integrity hooks. Related to #5154406

[test] run unittest_syncschema with postgresql Lets us test more things, since we can actually do ALTER TABLE.

[test] run unittest_migractions on postgresql sqlite's lack of support for a bunch of alter table functionality means some thing just don't get tested otherwise.

[devtools] Put pg sockets in /tmp Makes for shorter paths (limited by sockaddr_un). Also use the default port, since we're not listening on TCP sockets.

[devtools] change the way we start/stop postgresql Instead of having the test db handler start a cluster on demand, use the test module's setUp/tearDown callbacks to do it. This allows to have one data directory (and thus cluster) per test module, allowing different test modules to run in parallel, each using its own database cluster whose path is based on the test module.

[devtools] make test db name for postgresql process-specific In case we run two tests concurrently on the same cluster, better not use the same db name for both.

[devtools] extract functions to start/stop a postgresql cluster

[test] don't leave NULL columns around when making an attribute required It doesn't matter on sqlite (it doesn't do ALTER COLUMN), but when running this test on postgresql it fails to add the 'NOT NULL' constraint otherwise.

[server/session] Roll back in connection exit This was changed in commit 8b35a898b334 "[server] remove cnxset tracking, it is now unneeded". When exiting a CubicWeb Connection, the database connection is put back into the common pool. At that point anything done during the lifetime of the CubicWeb Connection needs to be committed or rolled back. Do a proper rollback to finish the transaction, as was happening before the above-mentionned commit. This showed up on testing with postgresql, when a DB schema modification was blocked by an old connection that was still "in transaction".

[web/views/formrenderer] do not use `cubicweb:target` attribute on form (closes #5534074) The `cubicweb:target` is a flag indicating that the form data (with file input) shall be posted inside an iframe - this is a well known "ajax-like" workaround to post files with browsers that do not support `FormData` (a.k.a IE<10). The `cubicweb:target` was introduced when CW used the "xhtml strict" doctype. Now that CW uses the "html5" doctype, this namespaced attribute is no longer necessary and the iframe can be generated directly. Before this patch, CW inserts the `cubicweb:target` attribute in the form DOM element (server side) and `setFormsTarget()` updates the DOM with a new `<iframe>` element (client side). Now, CW inserts the `<iframe>` DOM element directly (server side), making `setFormsTarget` useless.

[js] lint : make it explicit that typeof is an operator, not a function. Also, use === / !== except for null / undefined comparison

[devtools] qunit: show helpful data when an assertion fails Related to #5533333.

[web/test] Use shorter $() instead of jQuery() Consistency FTW. Related to #5533333.